Effect of pulsed electric fields on the antioxidant potential of apples stored at different temperatures

The effects of pulsed electric fields (PEF, 0.008–1.3 kJ kg−1) on the total phenolic, flavonoid and flavan-3-ol contents, as well as on the antioxidant capacity of apples stored at different temperatures (4 and 22 °C) along 48 h were studied. Contents of phenolic compounds observed in PEF-treated apples were higher than those of untreated. The mildest PEF treatment (0.008 kJ kg−1) produced the maximum increases of total phenolics (13%) and flavan-3-ol (92%) contents in apples stored during 24 h at 22 °C, while it was observed at 4 °C for flavonoids (58%). On the other hand, the antioxidant capacity of apples was enhanced by 43% respect to that of untreated with the mildest PEF treatment after 12 h at 4 °C and by 15% after 24 h at 22 °C. Therefore, PEF technology could be used to increase the antioxidant potential of apples by controlling treatment and storage conditions.This work was supported by the Spanish Institute of Agricultural and Food Research and Technology (INIA) (RTA2010-00079-C02-02) and the Spanish Ministry of Economy and Competitiveness (AGL2013-44851-R)